With the following share defined:
[share1]
path = /srv/share1
browseable = yes
read only = no
guest ok = no
inherit permissions = yes
I create a root directory:
mkdir inherit && chown 2770 inherit
I connect to the server with a Windows client and create a text file and a folder under that directory.
Here is what happens:
├── [drwxrws---] ./inherit
│ ├── [-rwxr-----] ./inherit/New text document.txt
│ └── [drwxrws---] ./inherit/New folder
According to the man page:
New files inherit their read/write bits from the parent directory.
In this case the containing folder group write permission has not been inherited.
The inheritance worked as expected in 4.1.6.